Uric Acid Lithiasis – A Study of Six Hundred and Twenty-Two Patients

Abstract

A clinical study is presented of 622 uric acid stone patients, constituting 34.6% of all patients with urolithiasis observed in a period of 12 years. The uric acid lithiasis in this series was essentially an upper urinary tract disease. Further evidence was obtained for idiopathic uric acid lithiasis being a disease entity, distinct from gouty uric acid lithiasis. Eighty percent of the uric acid stone patients were initially diagnosed as idiopathic uric acid lithiasis. Only 11 out of 359 patients with idiopathic uric acid lithiasis who came to follow up, developed gout. The majority of patients with idiopathic uric acid lithiasis were normouricemic and normouricosuric, only 13.6% of them became hyperuricemic during follow up. The male: female ratio in idiopathic uric acid lithiasis was 2.7:1, as compared with 12.3:1 in gouty uric acid lithiasis. In both the idiopathic and gouty uric acid lithiasis groups there was a preponderance of patients of European origin as compared with those of Near Eastern-Mediterranean origin. Myeloproliferative disease constituted a rare etiology in this series. There was a striking association of uric acid lithiasis with hyperparathyroidism, the latter occurring in 10.4% of the uric acid stone patients. Surgery and urinary tract infection was frequent.

Epidemiology of Urolithiasis

“…In Czechoslovakia they constitute % of all stones (HRADEC et al 1969), in Israel this figure is % (DE VRIES et al 1972;FRANK et al 1970) and in the Sudan over one-half (IBRAHIM 1979). In the series reported from the Soviet Union by TIKTINSKI (1979) 71 %of calculi consisted of uric acid and urates.…”

Citrate in Urine and Serum and Associated Variables in Subgroups of Urolithiasis

“…However, the latter may be subject to misclassification as either UA-I or N-C, depending on the urinary environment accompanying stone analysis from a given stone episode. Since in gouty populations some 12% have been found to produce calcium oxalate concretions [35], and since the sex ratio is 12:1 (<J/9) 'n the former [36] figures similar to our own -it may turn out that the majority of our low Cit subjects with uric acid stone formation (UA-I and UA-II) belong to larger populations with clini cally unapparent disturbances of purine metabolism such as urate overproduction or of renal handling of urate (in contrast to many gouty subjects urinary urate is normal in UA-I and UA-II [13]), manifesting as slightly elevated serum urate levels. Unfortunately, Cit studies in gouty subjects are virtually nonexistent.…”

Analysis of Urinary Calculi Formed by Nigerians

“…Analysis of 1,800 patients with urolithiasis in Israel showed the incidence of uric acid calculi to be 33% (Frank et al, 1970). The Sudan stones show more phosphate, less oxalate and more am monium acid urate compared to English stones.…”